Traditional railroad cars are designed to transport and dispense bulk material such as coal, stone, or other particulate material. Such railroad cars may include side dump or bottom dump railroad cars. Typical railroad dump cars are well-known in the art. A railroad dump car typically includes a receptacle for carrying bulk material and a railroad car frame. The railroad car frame may have a plurality of trucks, each truck comprising a plurality of wheels, axles, and bearings.
Typically, railroad cars used for transporting and dispensing bulk material are manufactured primarily of steel. The receptacle of a railroad car may have steel side and bottom panels that come into frequent contact with the bulk material. The use of steel in these panels poses certain disadvantages.
One disadvantage of the use of steel in railroad car construction is weight. Thick steel plating is typically used in railroad cars due to the abrasive nature of the bulk material carried in the railroad cars. Without such a durable material, the constant dumping and shifting of the bulk materials would wear through the panels in a short time, necessitating frequent repairs and resulting in costly delays. The use of thick steel plating may delay the necessity of repairs due to wear, but it adds a significant amount of weight to railroad cars. Many railroad cars are restricted to certain weight limits that include the payload weight plus the weight of the railroad car itself. Accordingly, any increase in a railroad car's weight may reduce the amount of payload it can carry and still stay within the weight limit.
Another disadvantage of traditional railroad car construction is carry-back. Carry-back, a phenomenon well-known in the art, occurs when bulk material being transported is frozen or damp, giving the material a propensity to amass into clumps and adhere to the railroad car's inside surfaces. Such clumps may remain stuck to the inside surface of the railroad cars even during dumping operations, thus reducing the amount of material dispensed and reducing the amount that can be subsequently loaded. Carry-back effectively reduces payload and increases the weight of the railroad car.
Another disadvantage of traditional railroad car construction is reduced wear resistance and/or durability. As noted above, thick steel plating is used due to the abrasive nature of different types of bulk materials. However, the steel plating still wears out over the course of normal usage of the railroad cars. When a portion of a railroad car has worn out, repairs can be costly and time-consuming. Resulting delays can add significantly to operating costs.
Yet another disadvantage is noise. As bulk materials are dumped into a steel railroad car, the resulting noise may be very loud, which may be harmful and/or disturbing to people in the vicinity. Another potential disadvantage is the jarring impact from dumping bulk material into a steel railroad car. This impact can increase wear on other components of the railroad car.
U.S. Pat. No. 4,116,485 to Svensson (“the '485 patent”) discloses a “bulk material carrying container defined by a framework including a base and a pair of opposing, generally parallel upright sides carried by the base.” The '485 patent further discloses an elastomeric sheet “that is secured to and suspended between the sides so that it forms a generally concave receptacle into which bulk material and the like may be dropped.” U.S. Pat. No. 6,068,927 to Stenman (“the '927 patent”) describes a “bulk material handling wear mat of elastomeric material having good wear and impact resistance” that “is suitable for use as a wear lining in haulage vehicles.” Notably, the '485 and '927 patents do not disclose any implementation of elastomeric materials in railroad cars and, in particular, do not disclose any configuration of elastomeric sheets in side or bottom dump railroad cars.
The present disclosure is directed to overcoming, or at least reducing, the effects of one or more of the issues set forth above.